Electromagnetic diffusion of a wall with modified checkerboard pattern

Recently, fifth-generation (5G) wireless communication systems have been spreading rapidly, and 5G mobile phone services started in 2020 in Japan. 5G wireless communication systems can provide not only greater capacities and higher speeds, but also ultrahigh-reliability, low latency, and multi-connectivity. Electromagnetic (EM) waves in the 28 GHz band are also used for 5G communications. At such high frequencies, only a few paths can reach a receiving antenna, owing to the high propagation loss and high directivity of antennas used. Consequently, when an obstacle, such as office partitions, exists in a room, the quality of wireless communications deteriorates abruptly in the blocked region. In this paper, we confirm the improvement in the diffusion characteristics of an EM scattering wall with a modified checkerboard pattern. We design and optimize an EM scattering wall that exhibits a wide EM diffusion characteristic for both TE and TM polarizations of incident fields.